David Evans wrote:

> OK, so it should work, and I'm not going mad.
> Background is that I have a Dilog SCSI controller at 172150 and an
>RQDX3 (with RX50) at 160334. Last night I wanted to boot XXDP and
>couldn't manage to get the machine to boot from floppy; even removing the
>SCSI controller didn't help. Anyway, I'll futz around with it some more
>and see what happens. I'm pretty sure that I did this exact thing back
>in January, though the RQDX3 may have been at 172150 then...I can't
>remember. Furthermore, I remember reading in the Sun Site archives
>about some confusion with DL11-style serial ports, so the DLVJ1 that I
>have plugged in may be causing grief.
> Thanks for the info.

For what it's worth, the whole unit number thing on MSCP devices has
caused me a bit of trouble when I have used two controllers. I believe
that the KDJ11-B firmware uses the unit number globally across all the
controllers. If you have 2 drives on the first controller as unit 0 and
1, and 1 drive on the second as unit 0, you might not be able to boot
unit 0 of the second controller.

My experience was with a CQD-220/M as the first MSCP controller and an
RQDX1 as the second. I had to set the starting unit jumpers of the
second controller to something greater than the number of units allotted
in the SCSI-MSCP firmware or I could not boot the floppy drives on the

I was using 2.11BSD and my reaction was to set the second controllers
unit start jumpers to start at unit 8. The BSD driver thought numbering
started at 0 and the controller thought it started at 8, so I could not
get at the floppies any more.

I believe that I set the second controller to start at unit 4. Then I
could boot the scsi drive on the first controller as DU0, and the floppy
on the second controller as DU4. In 2.11BSD, this was ra0 for the scsi
drive and ra12 (cntrlr*8 + u) for the floppy.


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